Characterization of chemical constituents in Zhi–Zi–Da–Huang decoction by ultra high performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry

A sensitive and reliable ultra high performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry method was established to separate and identify the chemical constituents of Zhi–Zi–Da–Huang decoction, a classic traditional Chinese medicine formula. The chromatographic separation was achieved on a Shim‐pack XR‐ODS C₁₈ column (75  × 3.0 mm, 2.2 μm) using a gradient elution program. The detection was performed on a Waters Xevo G2 Q‐TOF mass spectrometer equipped with electrospray ionization source in both positive and negative modes. With the optimized conditions, a total of 82 compounds were identified or tentatively characterized. Of the 82 compounds, 21 compounds were identified by comparing the retention time and MS data with reference standards, the rest were characterized by analyzing MS data and retrieving the reference literature. In addition, 31 compounds were identified from Gardenia jasminoides Ellis, ten compounds were identified from Rheum palmatum L., 33 compounds were identified from Citrus aurantium L., and eight compounds were identified from Sojae Semen Praeparatum. Results indicated that iridoids, anthraquinones, flavonoids, isoflavonoids, coumarins, glycosides of crocetin, monoterpenoids, and organic acids were major constituents in Zhi–Zi–Da–Huang decoction. It is concluded that the developed ultra high performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry method with high sensitivity and resolution is suitable for identifying and characterizing the chemical constituents of Zhi–Zi–Da–Huang decoction, and the analysis provides a helpful chemical basis for further research on Zhi–Zi–Da–Huang decoction.